Acute myeloid leukemia in childhood: fifteen-year experience in a single institution

Abstract

To investigate the survival of children with acute myeloid leukemia (AML) before and after the introduction of a Berlin-Frankfurt-Munich-83 based protocol. To analyze the prognostic impact of age, gender, nutritional status, initial white blood cell count and use of etoposide in the remission induction phase. This partly prospective/retrospective study comprised 83 children with AML diagnosed at Hospital das Clínicas, Universidade Federal de Minas Gerais, Brazil, between 1986 and 2000. Before 1991, 15 children were treated with 2-3 pulses of cytarabin plus daunomycin, followed by several consolidation/maintenance schemes. From January 1991 to November 1992 a pilot study (n = 15) was carried out to test etoposide toxicity in the induction phase. Etoposide was randomized from December 1992 to June 1999. Median follow-up period was 5 years. Initial remission rates were 40 and 66% before or after the introduction of the German protocol, respectively (p = 0.11). Induction failure was largely due to death caused by infection and/or hemorrhage. The 5-year estimated probabilities of survival and of continuous complete remission were 31+/-5.4% and 49.7+/-7.4%, respectively. All 22 relapses involved the bone marrow. Age below 6 years at diagnosis was significantly associated with a poor prognosis. Sex, initial leukocyte count, and nutritional variables were not significant prognostic factors. The randomized addition of etoposide in the induction phase unexpectedly decreased the probability of complete remission at 5 years. The introduction of a German-based protocol in 1991 significantly improved survival and duration of first remission. No plausible explanation for the unfavorable effect of etoposide was found.